American-Eurasian J. Agric. & Environ. Sci., 2 (4): 382-387, 2007 ISSN 1818-6769 © IDOSI Publications, 2007

Olea europaea L. A Botanical Contribution to Culture

Sophia Rhizopoulou

National and Kapodistrian University of Athens, Department of Biology, Section of Botany, Panepistimioupoli, Athens 157 84, Greece

Abstract: One of the oldest known cultivated plant species is Olea europaea L., the olive tree. The wild olive tree is an evergreen, long-lived species, wide-spread as a native plant in the Mediterranean province. This sacred tree of the goddess Athena is intimately linked with the civilizations which developed around the shores of the Mediterranean and makes a starting point for mythological and symbolic forms, as well as for tradition, cultivation, diet, health and culture. In modern times, the olive has spread widely over the world.

Key words: Olea • etymology • origin • cultivation • culture

INTRODUCTION Table 1: Classification of Olea ewopaea Superdivi&on Speimatophyta-seed plants

Olea europaea L. (Fig. 1 & Table 1) belongs to a Division Magnohophyta-flowenng plants genus of about 20-25 species in the family Oleaceae [1-3] Class Magn olio psi da- dicotyledons and it is one of the earliest cultivated plants. The olive Subclass Astendae- tree is an evergreen, slow-growing species, tolerant to Order Scrophulanale- drought stress and extremely long-lived, with a life Family Oleaceae- olive family expectancy of about 500 years. It is indicative that Genus Olea- olive Species Olea europaea L. -olive Theophrastus, 24 centuries ago, wrote: 'Perhaps we may say that the longest-lived tree is that which in all ways, is able to persist, as does the olive by its trunk, by its power of developing sidegrowth and by the fact its roots are so hard to destroy' [4, book IV. 13.5]. The most ancient traces of Olea are fossilised leaves, found on the island of Santorini in the Aegean Archipelago, dating back 50,000- 60,000 years [5, 6]. Olive cultivation originated in a valley of the river Jordan in the Eastern Mediterranean area [7] and has a history as long as that of western civilization [8,9]. Fig. 1: Olea europaea L., of the Linnean herbarium Sophocles (5th century BC) wrote a hymn to the olive (microfiche No: IDC 4.3, Department of tree, for his last play Oedipus at Colonos (401 BC): Phanerogamic Botany Swedish Museum of Natural History) • There is a plant unheard of in the fabulous land of Asia, The purpose of this study is to foster greater • unknown to Doric earth - a thing immortal; understanding of the botanical, historical and philological • gift of a goddess, beyond the control of hands, evidence for the origin and the distribution of the olive • tough, self-renewing, an enduring wealth, tree, 'the queen of all trees' according to Columella (Libri • passing through generations De Re Rustica, 42 AD). • the invincible grey-leafed olive. • Aged survivor of all vicissitudes, Botanical ancestor of Olea: The botanical ancestor of • it knows protection of the all-seeing eye of Zeus, the cultivated Olea europaea L. is believed to be a group • whose sunlight always regards it, of wild olives traditionally called oleaster olives. Over • and of grey-eyed Athena. large areas in the Mediterranean province, oleasters

thrive as a constituent of maquis formations, within a

Corresponding Author: Dr. Sophia Rhizopoulou, National and Kapodistrian University of Athens, Department of Biology, Section of Botany, Panepistimioupoli, Athens 157 84, Greece 382

Am-Euras. J. Agnc. &, Environ. Sci., 2 (4): 382-387, 2007 climatic region that has been defined by Koppen [10], as the olive climate [11-13]. Wild olive trees have been treated by some botanists as an independent species, i.e. Olea oleaster Hoffrn. & Link., but because of their close morphological and genetic affinities to the cultivated tree, most researchers dealing with Fig. 2: Olea, in Linear B (i.e. the first Greek writing Mediterranean plants today regard oleaster as the wild system) used between 14th and 12th century BC. race of the cultivated species and place it within Olea europaea L., either as a subspecies [subsp. oleaster (Hoffrn. & Link) Hegi], or as a variety [var. sylvestris South Africa. Olea europaea is now considered as an (Mill.) Lehr. = var. oleaster (Hoffm. & Link.) DC.] [2]. edible, medicinal and useful plant for a healthier world. Theophrastus (371-286 BC) stated that the wild olive tree It is noteworthy that olive oil contains 14.8% saturated differs from the cultivated olive in having spiny lower fat and 85.2% unsaturated fat [28] and it is valued as an branches [14, book V.12.8] and small leaves and drupes important item of diet [29]. Virgin olive oil, identified by its [4, book 1.14.2 & book II.2.12]. Cultivated and wild olive delicate and unique aroma [30], is highly appreciated by trees possess similar characteristics and it is difficult to consumers, because it is consumed in its crude form distinguish stands of wild olive trees [15-17]. According without any refining process. to archaeological evidence, Olea was cultivated in Crete and Syria, as long ago as 2,500 BC [18, 19]. Genetic Etymology of Olea: The first word for Olea appeared in studies support the hypothesis that olive domestication Linear B (Fig. 2), on clay tablets found in Greece dated to occurred in many locations in the Mediterranean basin the 13th century BC [31, 32]. The word olive and all the [20]. More recent work indicates that there must have surviving forms are derived from the Greek word elaa been a period of 'pre-domestication cultivation' in which (s/lcta), according to Theophrastus) and elam ( sAoua) the wild ancestors of domestic species were intentionally [33]. Thus, we have alev in Gothic, olia in old cultivated [21, 22]. The dimensions of carbonised stones Scandinavian, eel (oil) in Anglo-Saxon, olei (61) in old of Olea europeaea have proved to be an invaluable High German andofea, oliva, oleum, olivum in Latin [34]. parameter that can be used to distinguish between wild The Semitic word zeit for Olea is encountered in the and cultivated varieties [ 23-25]. Arabic zenboudje (wild olive) and zitoun (cultivated Olea europaea is a hermaphrodite tree that blossoms olive), in the Andalousian azenbucha, in the Portuguese in spring; two kinds of small, fragrant, cream-coloured zambugeiro, in the word zayit in Israel and zuitin in flowers produce pollen, the species being largely wind Morocco; it is interesting to note that among the Tuaregs pollinated, though, most olive varieties are self-fertile. The the wild olive is called aleo [32]. fruit of the olive tree is a drupe that usually changes It would seem that a relationship in definition colour from green to purple or nearly black, when fully between the word for oil (eleon) and the word for mercy ripe in late autumn and the oil is expressed by the fleshy (eleos) in Greek, might be due to a false etymology [35]. pericarp. Pliny (23-76 AD) refers to Historia Naturalis However, in dramatic masterpiece-texts such as Oedipus (XE.14, XE.60, XV.1-7, XXm.34-60) fifteen varieties of Rex of Sophocles (434 BC) a person who came in olives and the usefulness of olive oil. The varieties supplication, seeking mercy and understanding from his known to the modern farmer are numerous, because follow-men, when he had committed a grave offence, olive trees have been exclusively cross-pollinated. The holds olive branches in his hands. In Eumenides of cultivars vary considerably in size, shape, oil content and Aeschylus (5th century BC), the soothsayer Pythia of the flavour and molecular markers have been used to classify Delphi oracle announces 'I see a man with bloody them [26, 27]. hands seated at the Navel, postured in the suppliant's The cultivation of olive trees has been expanded to seat, holding a fresh stem of olive'. Olive trees were Egypt, France Iberia, Israel, Italy, Lebanon, Morocco and closely planted in Delphi valley from very ancient times. Tunis. Olive trees have been introduced to Chile, the In the Shakespeare's TwelfthNight of (1.5.204) 'I bring no Caribbean, Peru, Argentina, Brazil, Mexico and finally, overture of war, no taxation of homage, I hold the olive in the 17th century, to California. The olive tree has in my hand: my words are as full of peace as matter'. also been introduced into Chinese agriculture and it Therefore, it is likely that olive branch has been a symbol grows vigorously in South Australia and some parts of of peace and of the reconciliation of man with man.

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In this spirit, olive branches appear in the flag of the Epidaurians). In fact, Theophrastus writes that olive- United Nations Organization and have became a symbol wood is more apt than other woods to produce shoots of longevity, purification, strength, prosperity, wisdom, even when lying idle or made into manufactured victory and peace. It is well known that in the Olympic articles; this it often does, if it obtains moisture and lies in games, the winners were crowned with wreaths made of a damp place [4, book V.9.8]. The olive tree long stood on olive branches [36]. the Acropolis and, though destroyed in the Persian invasion (480 BC), sprouted again from its root [41]. To Olea in the (early) civilizedmediterranean province: the long-lived character of olea, both cultivated and Olea europaea appears in the Bible and in the Qur'an, as wild witness is born also by the tales handed down in the most sacred, most revered and most adored tree, mythology, as the olive at Athens [4, book IV.13.2). playing an important role in civilization, religion, diet and Anstotle (384-322 BC) tells us that even the death penalty art. Olea was cultivated during the early Biblical period for could be imposed on a person who uprooted or destroyed the fruits from which precious oil was extracted, while a sacred olive tree. Those trees, later totally twisted olives were treated with pickling and salting techniques (hunchbacked), being extremely old, were growing in the for domestic and export purposes [37]. Olive trees have Academy, still in existence at the time of Pausamas (2nd been cultivated along and above the 15° isotherm century AD). It appears that the life of the individual providing a useful substitute for the butter and animal olive (in regard to which one should make the trunk the fats consumed by the races of the north. Hence, the olive essential part and standard in estimating the time) lasts for became an emblem of national wealth and domestic about two hundred years [4, book IV.13.5]. plenty [19]. 'The whole Mediterranean seems to emerge The town of Athens was surrounded by extensive from the pungent taste of black olives, a taste older olive groves down to the times of Ottoman rule, as was than that of meat and wine; a primeval taste, like the taste witnessed by travellers [42-44]; among them John of water' [38]. Sibthorp (Professor of Botany in Oxford, 1784-1796), Sir The species was known in ancient Egypt, as is J. E. Smith (the first president of the Linnean Society) and shown by papyri (1,550 BC), mummies crowned with olive J. Lindley (a great East Anglian botanist) passed through wreaths and a hymn of Ram esses IE (1198-1176 BC) to the a venerable forest of olives during a trip to Athens, in god Ra (the sun): 'I have planted many olive trees in 1787 [45, 46]. Excavation of the Athenian Agora (1931- gardens, in the city of Heliopohs; from these plants come 1970) has uncovered evidence for abundant olive plants a very pure oil to keep alight the lamps of your altaf [39]. in antiquity [47]. In the Iliad and Odyssey of Homer (written before 700 BC), Material evidence of the extent of olive oil trade olive oil provides extensive power when used in ritual is plentiful. Thousands of small oil lamps have been anointing. The species was, also, known in Armenia [1]. found in Greece, during the Bronze Age (2800-1100 BC). Roman people employed it largely in food and cookery; In the first stepped Pyramid (known as the Mastaba of in the luxurious days of the later empire it became a Sakkara), a representation of one of the earliest known favourite axiom that long and pleasant life depends on oil presses exists. In the palace of Minos in Crete an two fluids 'wine within and oil without' [40, book olive press was in operation (2000-1000 BC). The XXIV. 150). Srabo the geographer (63 BC-23 AD) and Athenian pottery industry was stimulated largely by Columella in his Libri De Re Rustica (42 AD) mentioned the demand for containers in which olive oil was the quality of Spanish oil. exported. Oil of the sacred trees was put into black-figure amphorae, decorated with olive-harvest motives. Olea from mythology to the early history of plants: The Perfumers put their odours in oil [14, book VI. 19.3] and city of Athens was named after the goddess Athena, who small vessels with scented olive oil were one of the brought the olive tree to the city. When Athena won the most favourite love gifts [5]. Oil in phials was used as a contest against Poseidon for the patronage of the city, an cleanser for the body, just like soap nowadays [18]. olive sprang from the barren rock of Acropolis at the Samples of oil vessel (lekythos) with a depiction of a siren bidding of the goddess. That this myth has some in front of an olive branch are exhibited in Museums and relation to the first planting of the olive tree in Greece Art Galleries. seems certain according to Herodotus (485-425 BC,

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Olea europaea as an inspiration in art and research: from the era of Greek and Egyptian civilizations, in which From myth into history and from there into art and the olive tree was a divine gift for the mortals [67], to the research, Olea europaea has come to occupy a dominant century of globalisation, Olea europaea remains a place in our lives peacefully. Olive trees, features of the symbolic element of plenty, peace and serenity [37]. Mediterranean landscape, have inspired artists, who tried to capture the emerald and silver hues of the leaves ACKNOWLEDGEMENTS shimmering against an azure Mediterranean sky or the gnarled and twisted branches that withstand the ages. In I wish to thank Prof. P. Valavanis for comments on Italy, Pohphiho in Hypnerotomachia [48], during a literature and Danae Koukos for comments on an earlier fantastic journey of love through gardens, found himself draft of the manuscript. in a dream 'I was encircled by pleasant hills of no great height with wild olives disposed according to the aspect REFERENCES of forested slopes'. In Iran, nearly four centuries later (1994), an olive grove is magnified as a place of desire and 1. Moazzo, G.P., 1994. Les plantes d' Homere et de unsatisfied meeting, in the multi-awarded film of Abbas quelques autres poetes de 1' antiquite: V. L' Olivier Kiarostami entitled 'Through the olive tree'. (Elaie). Ann. Musei Goulandris, 9: 185-233. Impressionists were especially enamoured of the beauty 2. Zohary, D. and M. Hopf, 2000. Domestication of of olive trees, which were vigorously painted by Vincent plants in the Old world. Clarendon Press. van Gogh (1853-1890). Writing to his brother Theodore 3. Riley, F.R., 2002. Olive oil production onBronze Age (letter 587, April 1889), van Gogh stated 'I am struggling Crete: nutritional properties, processing methods to capture the light of the olives. It is silver, sometimes and storage life of Minoan olive oil. Oxford J. bluish, sometimes greenish, off-white, on a ground of Archaeol.,21: 63-75. yellow, pink, violet, or orange to red ochre. It is very 4. Theophrastus, 1926. Fourth century B.C. Enquiry difficult' [49]. A couple of months later (letter 595, lune into plants (vol. I, II) in ancient Greek. Hort AF 1889), Vincent declared: 'At last, I have a landscape with (translator) 1926. Loeb classical library. Cambridge: olive trees'. Heinemann London and Harvard University Press. Olea europaea has evolved a number of adaptive 5. Valavanis, P., 2004. Olive oil and the ancient mechanisms to survive the prolonged summer-drought Greeks. In Ode to the olive tree. Academy of Athens, conditions in the Mediterranean environment, which pp: 62-73. 6. Velitzelos, E. and D. Velitzelos, 2005. Geohistorical affect water status and CO2 assimilation [50, 51]. Its leaves expand within three months, during spring and are evidence on the evolution of plants in the Aegean replaced after a two-year life period [52, 53]; a second Sea. In Biodiversity and natural heritage in the growth flush occurs in autumn [54]. Their capacity to Aegean, Eds., Karamanos, A.J. and C.A. Thanos. undergo dehydration is limited by a high internal diffusive The Agricultural University of Athens, pp: 133-148. resistance, which is due to the dense packing of 7. Zohary, D. and P. Spiegel-Roy, 1975. Beginnings mesophyll cells [55, 56]. A layer of peltate scales on the of fruit growing in the old world. Science, 187: abaxial leaf surface may intercept incoming irradiation and 319-327. 8. Forbes, H. and L. Foxhall, 1978. The queen of all impede the diffusion of CO2 into the leaf. These scales are likely to function by trapping warm moist air below the trees. Preliminary notes on the archaeology of the stomatal aperture and consequently reducing water loss olive. Expedition, 21: 37-47. from the plant [57-60]. The species has been studied as a 9. Oliveira, I., R.M. Tavares and H. Geros, 2002. predictor of climate change [61]. Its stomatal density, Utilization and transport of glucose in Olea investigated in leaf-samples originating from europaea cell suspensions. Plant Cell Physiol., Tutankhamun's tomb (1327 BC) and from material dating 43: 1510-1517. to 332 BC, 1818 and 1978 AD, was used as an indicator 10. Koppen, W., 1923. Die Klimate der Erde. De Gruyter. 11. Specht, L. and I.E. Moll, 1983. Mediterranean-type of the effect of rising, atmospheric CO2 levels in leaf structure and function [62, 63]. Recently, airborne pollen heathlands and sclerophyllous shrublands of the concentration, reflecting the flower phenology of olive world: an overview. In Mediterranean-type populations within a radius of 50 km, has been considered ecosystems, Eds., Kruger F.I., D.T. Mitchell and as a sensitive indicator of climatic warming [64-66]. Yet J.U.M. Jarvis, Srpinger-Verlag, pp: 41-65.

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